Fans of the sitcom Friends will no doubt remember the episode called “The One with the Jellyfish”, where Monica is stung while on a trip to the beach. Joey remembers a Discovery Channel programme on how urine can help stings and bites, and so being a true friend he offers to pee on the sting for her. Unfortunately he gets stage fright and cannot squeeze out a drop, leaving Chandler to do the heroic deed.

As with Monica’s jellyfish sting, you often hear that urine helps with snakebites, and indeed BBC World Service listeners from Cameroon, Sri Lanka and Burma have been in touch with me to ask whether this is true.

Before I explore this myth further, here are some quick facts and figures about snakebites. As many as five million people are bitten by snakes every year, many of them in sub-Saharan Africa, and South and South East Asia. The good news is that only a small minority of those bites are fatal. The bad news is that this still means 125,000 people are killed by snakebites every year, half of whom are in India.

Avoidance tactics

It might seem blindingly obvious, but the first piece of advice given by reptile and amphibian experts (or herpetologists, to give them their formal name) is to try to avoid getting bitten in the first place. Leave snakes alone if you see them, wear long trousers and shoes or boots in areas where they are common and shake out your footwear before putting them on in case there’s a snake hiding inside.

But even with these precautions it is still possible to encounter a snake accidentally. In Costa Rica last year I was shown poisonous yellow eyelash vipers, which camouflage themselves perfectly by weaving in and out the yellow and red blooms of heliconia plants. The flowers are so beautiful that visitors often touch them admiringly and occasionally to their horror find themselves holding a poisonous snake.

So if you get bitten, should you somehow find a way to urinate on the bite? The simple answer is no, because this will waste valuable time that would be better used getting you to the nearest hospital to receive antivenom. It is not that urine is useless, it just doesn’t help snakebites. Urine contains urea, which softens the skin and is contained in many creams, such as those for cracked heels. It is also an antiseptic, which is why some people find it helpful to bathe leg ulcers in urine. But even these qualities are not enough to help neutralise the toxins in snake venom.

So if urination does not help, how about other popular claims, like sucking out the venom or tearing up your shirt to make a tourniquet to stop the poison spreading?

Unfortunately, sucking out the venom will not work either, because you are unlikely to get all of it out before it begins to spread. Even trying to cut the bite out with a knife can increase the risk of severe bleeding, as the venom may already be stopping the blood from clotting properly. Tourniquets used to be recommended, but they can damage the tissue surrounding the bite. However, it is worth gently immobilising the limb in the same way you would if it was broken, because the less the limb moves, the slower the spread of the venom.

Leave it!

Do not endanger yourself or waste time by killing the snake to take to the hospital for identification, but any distinctive features you can remember will help the staff to assess whether it might be poisonous. What markings did you see? What shape were the eyes? Did you see fangs? What shape was the head? Were there pits between the eyes and nose? If the snake is dead you could take it with you, but do not handle its head. It may still bite you on reflex, even when dead, so it is usually best to take a picture with your phone instead.

One man who is determined to reduce the number of deaths from snakebite in India is Dr Ian Simpson, a British herpetologist who has worked with the WHO and helped to draw up India’s first national protocol for treating snakebites. The idea is to get antivenom out to rural areas, because delays in reaching hospitals are the biggest cause of death. He is frustrated by the number of people he meets who go to traditional healers for treatment instead of heading straight to hospital. Many people visit healers and subsequently recover from their bites, but Simpson says this is because the majority of snakebites are not actually poisonous.

In Costa Rica a biologist gave me one last piece of advice about what to do if bitten by a snake. The poison circulates around the body in your bloodstream, so the lower you can keep your heart rate, the slower the poison will spread around your body. His advice is to keep very calm on your way to hospital so that your heart does not begin to race, despite knowing you have received a bite that could prove lethal. Good luck with that one!

DisclaimerAll content within this column is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. The BBC is not responsible or liable for any diagnosis made by a user based on the content of this site. The BBC is not liable for the contents of any external internet sites listed, nor does it endorse any commercial product or service mentioned or advised on any of the sites. Always consult your own GP if you're in any way concerned about your health.